package com.ljm.shiro.filter;

import org.springframework.stereotype.Component;

import javax.servlet.*;
import javax.servlet.annotation.WebFilter;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;
import java.io.PrintWriter;

/**
 * 跨域处理
 */
@Component
@WebFilter(urlPatterns = "/*", filterName = "corsFilter")
public class CorsFilter implements Filter {

    @Override
    public void doFilter(ServletRequest req, ServletResponse res, FilterChain chain) throws IOException, ServletException {
        HttpServletResponse response = (HttpServletResponse) res;
        HttpServletRequest request = (HttpServletRequest) req;
        response.setHeader("Access-Control-Allow-Origin", request.getHeader("Origin"));
        response.setHeader("Access-Control-Allow-Credentials", "true");
        response.setHeader("Access-Control-Allow-Methods", "GET,HEAD,POST,PUT,PATCH,DELETE,OPTIONS,TRACE");
        response.setHeader("Access-Control-Max-Age", "3600");
        response.setHeader("Access-Control-Allow-Headers", " Origin, X-Requested-With, Content-Type, Accept,x-token,ljmtoken");
        if ("OPTIONS".equalsIgnoreCase(request.getMethod())) {
            PrintWriter printWriter = response.getWriter();
            printWriter.write("true");
            printWriter.flush();
        } else {
            chain.doFilter(req, res);
        }
    }
}
